Radiological Characteristics of Patients With Anti-MDA5-Antibody-Positive Dermatomyositis in 18F-FDG PET/CT: A Pilot Study

Heng Cao; Junyu Liang; Danyi Xu; Yinuo Liu; Yinan Yao; Yiduo Sun; Ye He; Jin Lin

doi:10.3389/fmed.2021.779272

Radiological Characteristics of Patients With Anti-MDA5-Antibody-Positive Dermatomyositis in ¹⁸F-FDG PET/CT: A Pilot Study

Front Med (Lausanne). 2021 Nov 22:8:779272. doi: 10.3389/fmed.2021.779272. eCollection 2021.

Authors

Heng Cao¹, Junyu Liang¹, Danyi Xu¹, Yinuo Liu², Yinan Yao³, Yiduo Sun¹, Ye He¹, Jin Lin¹

Affiliations

¹ Department of Rheumatology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
² PET Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
³ Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.

Abstract

Objective: To elucidate the ¹⁸F-fluorodeoxyglucose (FDG) PET/CT characteristics and its prognostic value in the patients with anti-melanoma differentiation associated protein 5 antibody positive (anti-MDA5+) dermatomyositis (DM). Methods: This retrospective cross-sectional study included 26 patients with anti-MDA5+ DM and 43 patients with anti-MDA5 negative (anti-MDA5-) idiopathic inflammatory myopathy (IIM) who were examined by ¹⁸F-FDG PET/CT from January 1, 2017 to December 31, 2020. The maximum standardized uptake value (SUVmax) of multiple organs and other clinical characteristics of the patients were measured and analyzed. Results: Compared with the anti-MDA5- group, the patients in the anti-MDA5+ group showed higher bilateral lung SUVmax (p = 0.029), higher SUVmax of spleen (p = 0.011), and bone marrow (p = 0.048). Significant correlations between the spleen SUVmax and serum ferritin levels (r = 0.398, p < 0.001), erythrocyte sedimentation rate (ESR) (r = 0.274, p = 0.023), platelet count (r = -0.265, p= 0.028), myositis disease activity assessment score (r = 0.332, p = 0.005), bone marrow SUVmax (r = 0.564, p < 0.001), and bilateral lung SUVmax (r = 0.393, p < 0.001) were observed. Conclusion: ¹⁸F-FDG PET/CT was found valuable in quantifying the pulmonary focal inflammation and potentially unveil the distinctive characteristics and pathophysiological mechanisms in the patients with anti-MDA5+ DM.

Keywords: 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT); dermatomyositis; interstitial lung disease (ILD); melanoma differentiation associated protein 5 (MDA5); standardized uptake value (SUV).